A072076 Largest k such that EulerPhi(k) = 10^n.

2, 22, 250, 3750, 41250, 414150, 4166250, 42281250, 438281250, 4400343750, 44266406250, 449238281250, 4510352343750, 45373066406250, 455545586718750, 4555455867187500, 45555287544813750, 455552875448137500, 4566844506855468750, 45668445068554687500

Offset: 0

Author

Labos Elemer, Jun 13 2002

Keywords

• nonn

Examples

			n=3: a(3)=3750 because InvPhi(1000) = {1111, 1255, 1375, 1875, 2008, 2222, 2500, 2510, 2750, 3012, 3750}.
		

Links

• Ray Chandler, Table of n, a(n) for n = 0..1000
• Max A. Alekseyev, Computing the Inverses, their Power Sums, and Extrema for Euler's Totient and Other Multiplicative Functions. Journal of Integer Sequences, Vol. 19 (2016), Article 16.5.2

Crossrefs

Cf. A000010, A014197, A014573, A072074, A072075, A110076.

Formula

a(n) = Max{k; A000010(k) = 10^n}.

Extensions

More terms from Max Alekseyev, Apr 26 2010